[with patch, positive review] Sequence doesn't know how to typeset itself

[burcin]

It seems that Sequence objects forgot how to typeset themselves somewhere between 3.4.2 and 4.1.

In 3.4.2:

sage: res = solve(x^2-2,x)
sage: latex(res)

\left[x  =  -\sqrt{ 2 }, 
 x  =  \sqrt{ 2 }\right]

In 4.1:

sage: latex(res)

\text{[
x == -sqrt(2),
x == sqrt(2)
]}
sage: latex(res[0])
x = -\sqrt{2}

Attached patch adds a _latex_ method to sage.structure.sequence.Sequence.

[burcin]

Trac doesn't let me upload the patch. Here it is if anybody wants to review it in the meantime:

 http://sage.math.washington.edu/home/burcin/trac_6677-sequence_latex.patch

[jhpalmieri]

Okay, I see why this used to work and doesn't anymore: we used to test elements when formatting for LaTeX using isinstance(x, list), and sequences returned True for this. Now we test using type(x) and looking it up in a dictionary, and there is no entry for "sage.structure.sequence.Sequence". The patch here solves the problem for sequences and includes a doctest. I have a trivial referee's patch (adds 'r' to the triple quotes at the beginning of the docstring, since there are backslashes in it).

[jhpalmieri]

apply on top of the other patch

[mvngu]

Merged both patches.